Sensor packages are known and are generally assembled onto a lead frame structure along with several other sensor packages in close proximity, such as on a substrate. The lead frame provides electrical interconnections to a semiconductor die. In general, the die is attached to a lead frame and then bonding pads of the die are electrically connected to leads of the lead frame, typically with wires using a wire bonding process. The assembled sensor packages must be separated at some point such that they can be individually implemented into various systems or circuit boards.
FIGS. 1 to 4 illustrate a known method of assembling sensor packages. FIG. 1 illustrates a metal lead frame 50 having plated with a wire bondable material 52. FIG. 2 shows the plated lead frame 50 premolded with a molding compound 54. The molding compound forms cavities 56, where each cavity 56 includes an exposed die pad 58 and exposed leads 60. The cavities 56 are separated by strips of molding compound 54. The cavities are then singulated using a saw making cuts 62 as shown in FIG. 3. In general, the cutting process generates dust and heats up the saw blade. Accordingly, pressurized water or some other means would need to be used to cool the blade and removed the dust.
After the water is removed from the singulated units, the units are reconstituted onto a temporary carrier 64 for further assembly. A die 66 is attached to the die pad 58 and wires 68 are bonded to the die 66 and the leads 60 to form an electrical connection. After final assembly, the sensor packages are removed from the temporary carrier 64 for installation on a board or other device.